Sheet conveying device and image forming apparatus including sheet holding mechanism capable of holding sheet against movement away from sheet alignment plate

Abstract

A sheet conveying device includes a sheet conveyance path, a conveyance roller, an alignment plate, an alignment roller, and a sheet holding mechanism. The conveyance roller conveys a sheet along the sheet conveyance path. The alignment plate is provided at one end of the sheet conveyance path in a direction orthogonal to a direction of conveyance of the sheet and in parallel with the direction of conveyance of the sheet and aligns a position of the sheet in the direction orthogonal to the direction of conveyance. The alignment roller rotates in the direction orthogonal to the direction of conveyance while making contact with the sheet present in the sheet conveyance path, thus bringing the sheet into abutment on the alignment plate. The sheet holding mechanism makes contact from above with the sheet present in the sheet conveyance path to hold the sheet against movement away from the alignment plate.

What is claimed is: 
     
         1 . A sheet conveying device comprising:
 a sheet conveyance path;   a conveyance roller that conveys a sheet along the sheet conveyance path;   an alignment plate that is provided at one end of the sheet conveyance path in a direction orthogonal to a direction of conveyance of the sheet and in parallel with the direction of conveyance of the sheet and aligns a position of the sheet in the direction orthogonal to the direction of conveyance;   an alignment roller that rotates in the direction orthogonal to the direction of conveyance while making contact with the sheet present in the sheet conveyance path, thus bringing the sheet into abutment on the alignment plate; and   a sheet holding mechanism that makes contact from above with the sheet present in the sheet conveyance path to hold the sheet against movement away from the alignment plate.   
     
     
         2 . The sheet conveying device according to  claim 1 , wherein the sheet holding mechanism comprises a sheet holding roller that rotates with movement of the sheet toward the alignment plate, but keeps from rotating in a direction of movement of the sheet away from the alignment plate. 
     
     
         3 . The sheet conveying device according to  claim 2 , wherein the sheet holding roller comprises a cylindrical one-way clutch and an elastic body covering a periphery of the one-way clutch. 
     
     
         4 . The sheet conveying device according to  claim 2 , wherein the sheet holding roller is provided near the alignment roller. 
     
     
         5 . The sheet conveying device according to  claim 2 , wherein
 the sheet holding mechanism further comprises a frame that includes a pair of side portions opposed to each other and a connecting portion connecting between the pair of side portions and thus has a C-shaped cross section,   the alignment roller is provided between the pair of side portions to project partly beyond an opening of the C-shaped cross section of the frame, and   the sheet holding roller is mounted to one of the pair of side portions to project partly beyond the one side portion along a direction toward which the opening of the C-shaped cross section of the frame opens.   
     
     
         6 . An image forming apparatus comprising:
 the sheet conveying device according to  claim 1 ; and   an image forming device that forms an image on the sheet being conveyed by the conveyance roller.